diff -r b9f51f49bf2a -r 9eba72cdde34 mercurial/wireproto.py
--- a/mercurial/wireproto.py	Wed Apr 25 17:04:18 2012 +0200
+++ b/mercurial/wireproto.py	Thu Apr 26 03:47:17 2012 +0200
@@ -555,7 +555,7 @@
     their_heads = decodelist(heads)
 
     def check_heads():
-        heads = repo.heads()
+        heads = phases.visibleheads(repo)
         heads_hash = util.sha1(''.join(sorted(heads))).digest()
         return (their_heads == ['force'] or their_heads == heads or
                 their_heads == ['hashed', heads_hash])